<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>基于弹性布局,实现典型的页面结构</title>
</head>

<body>

  <style>
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }

    .nav {
      width: 100%;
      height: 50px;
      background-color: rgb(60, 60, 60);
      color: white;
      text-align: center;
      line-height: 50px;
      font-size: 20px;
    }

    .container {
      width: 100%;
      height: 1000px;

      background-color: gray;
      display: flex;
      justify-content: center;
      align-items: center;

    }

    .container .left,
    .container .right {
      width: 20%;
      height: 100%;
      background-color: rgb(47, 157, 47);
      font-size: 20px;
      line-height: 1000px;
      text-align: center;
      color: white;
    }

    .container .content {
      width: 60%;
      height: 100%;
      background-color: rgb(135, 130, 130);
      font-size: 20px;
      line-height: 1000px;
      text-align: center;
      color: white;
    }

    .footer {
      width: 100%;
      height: 150px;
      background-color: rgb(60, 60, 60);
      color: white;

      font-size: 20px;
      text-align: center;
      color: white;
    }
  </style>


  <div class="nav">
    导航栏
  </div>
  <div class="container">
    <div clas s="left">
      左侧边栏
    </div>
    <div class="content">
      内容区域
    </div>
    <div class="right">
      右侧边栏
    </div>
  </div>
  <div class="footer">
    页脚
  </div>


</body>

</html>